FOR half a century Agnes Martin was a serene and luminous presence in American art. No painter has shown as convincingly that less, in artistic terms, can sometimes be so much more.

At a glance, or from a distance, her work looks like nothing at all. Square canvases are so palely touched with colour they might almost be blank. Considered slowly and carefully and close-up, however, the whole surface comes alive. Every detail counts, as the viewer is gripped by an intricate and endlessly fascinating interplay of irregular graphite lines and thinly layered bands or strokes of paint.

The restraint and formal regularity of Martin’s work has led her often to be grouped with the Minimalists. She shares something of their self-effacing rigour and their concern with the material qualities of art, but she herself preferred to be seen in the context of the Abstract Expressionist painters who were her own contemporaries and early artistic models. Like them she may have seen abstract art as the means to a distinctively American sublime, derived, however remotely, from the urban landscape of New York or the vast open spaces of the Midwest and underpinned, coherently or not, by a blend of Eastern wisdom and the Yankee transcendentalism of Emerson and Thoreau.

Martin’s art, however, is quite free of the bombast, machismo and self-regard that can make the efforts of her Abstract Expressionist peers seem wearying at times. Instead it is meticulous, human, contemplative and often full of joy. “Art is the concrete representation of our most subtle feelings,” she said. Her delicate, finely wrought paintings are abstract but full of emotion, both a record of their own inspired production, and a celebration of the experience of being in the world.

Agnes Bernice Martin was born in Macklin, Saskatchewan, in 1912, to a family of Scottish Presbyterian pioneers. Her father, a wheat farmer, died when she was two, and she grew up first in Calgary, Alberta, then in Vancouver, where her mother supported the family by renovating and selling old properties. Her maternal grandfather was a great influence, a gentle, religious man. The Bible and Pilgrim’s Progress were her earliest books. The first picture she bought was a postcard-sized print of The Angelus by Millet. She and her older brother liked to draw.

In 1931, aged 19, she moved to the US, to train as a teacher. She qualified at the Western Washington College of Education in Bellingham, Washington State, and then went on to Teachers College, Columbia University, New York. Study was interspersed with periods of classroom work. She became a US citizen in 1950.

It was in New York that she began seriously to paint and draw and became aware of the work being done there by her contemporaries the Abstract Expressionists. It was there, too, that she first became interested in Eastern thought, attending lectures by Krishnamurti and the Zen scholar D. T. Suzuki. Some of these ideas would influence her for the rest of her life.

Her career as an artist acquired new impetus and direction from a period spent studying and teaching at the University of New Mexico at Albuquerque. A summer study programme took her in 1947 to the university’s Field School of Art in Taos, a remote small town at the foot of the Sangre de Cristo mountains in northern New Mexico.

With its clear, bright light and clean air, its mixed Hispanic and Native American heritage, and the rich earth tones of its old adobe buildings, Taos had been a magnet for artists since the last years of the 19th century. D. H. Lawrence famously spent time there in the 1920s. “Never shall I forget the Christmas dances at Taos,” he wrote, “twilight, snow, the darkness coming over the great wintry mountains and the lonely pueblo.”

Martin had her first exhibition in Taos, in June 1947 at the Harwood Museum. She lived in the town for five years from 1952, with occasional returns to New York to pursue her graduate studies. She relished the strange beauty of New Mexico’s desert landscape, but she relished, too, that “it was the second poorest state in the Union, and everything was so cheap”. Unable to sell her work, she endured conditions of some hardship, living as well as working in the studio that she rented for $15 a month.

All this changed in the mid-1950s when her work came to the attention of the Manhattan gallerist Betty Parsons, who had on her books most of the leading avant-garde American artists of the day. She offered Martin a solo exhibition, on condition that she move to New York.

Martin, reluctantly, agreed, and in 1957 she found a derelict 19th-century sailmaker’s loft on Coentis Slip, near Wall Street in Lower Manhattan. It looked out on to the river, she recalled, but it was in such poor condition “that it was against the law to live in it”. She put the plumbing in herself. Fellow residents of the area included Ellsworth Kelly, Robert Rauschenberg, Robert Indiana and Jasper Johns.

In New Mexico, Martin, like many of her contemporaries, had been working in a vaguely Surrealist semi- abstract style, using forms still clearly derived from the organic world. In New York, her paintings soon showed the influence of the Abstract Expressionists who were her neighbours or gallery stablemates.